diff --git a/Network/HTTP/Proxy.hs b/Network/HTTP/Proxy.hs
--- a/Network/HTTP/Proxy.hs
+++ b/Network/HTTP/Proxy.hs
@@ -17,7 +17,7 @@
 ---------------------------------------------------------
 
 -- | This module contains a simple HTTP and HTTPS proxy. In the most basic
--- setup, the caller specifies a port and runds it as follows:
+-- setup, the caller specifies a port and runs it as follows:
 --
 -- > -- Run a HTTPS and HTTPS proxy on port 3128.
 -- > import Network.HTTP.Proxy
@@ -33,6 +33,7 @@
 
     , Settings (..)
     , defaultSettings
+    , Request (..)
     )
 where
 
@@ -152,6 +153,7 @@
 runSettingsSocket :: Settings -> Socket -> IO ()
 runSettingsSocket set sock = do
     let onE = proxyOnException set
+        reqRM = proxyRequestModifier set
         port = proxyPort set
     tm <- T.initialize $ proxyTimeout set * 1000000
     mgr <- HE.newManager
@@ -159,7 +161,7 @@
         (conn, sa) <- accept sock
         _ <- forkIO $ do
             th <- T.registerKillThread tm
-            serveConnection th tm onE port conn sa mgr
+            serveConnection th tm onE reqRM port conn sa mgr
             T.cancel th
         return ()
 
@@ -196,10 +198,11 @@
 serveConnection :: T.Handle
                 -> T.Manager
                 -> (SomeException -> IO ())
+                -> (Request -> IO Request)
                 -> Port -> Socket -> SockAddr
                 -> HE.Manager
                 -> IO ()
-serveConnection th tm onException port conn remoteHost' mgr = do
+serveConnection th tm onException requestMod port conn remoteHost' mgr = do
       mExtraSocket <- E.run_ (fromClient $$ serveConnection')
           `finally` sCloseX conn
       case mExtraSocket of
@@ -217,7 +220,7 @@
         --liftIO $ print $ requestHeaders req
         case req of
             _ | requestMethod req `elem` [ "GET", "POST" ] ->
-                proxyPlain req
+                liftIO (requestMod req) >>= proxyPlain
             _ | requestMethod req == "CONNECT" ->
                 case B.split ':' (rawPathInfo req) of
                     [h, p] -> proxyConnect th tm onException conn h (readDecimal $ B.unpack p) req
@@ -551,6 +554,7 @@
     , proxyHost :: String -- ^ Host to bind to, or * for all. Default value: *
     , proxyOnException :: SomeException -> IO () -- ^ What to do with exceptions thrown by either the application or server. Default: ignore server-generated exceptions (see 'InvalidRequest') and print application-generated applications to stderr.
     , proxyTimeout :: Int -- ^ Timeout value in seconds. Default value: 30
+    , proxyRequestModifier :: Request -> IO Request -- ^ A function that allows the the request to be modified before being run. Default: 'return . id'.
     }
 
 -- | The default settings for the Proxy server. See the individual settings for
@@ -566,6 +570,7 @@
                 when (go' $ fromException e)
                     $ hPutStrLn stderr $ show e
     , proxyTimeout = 30
+    , proxyRequestModifier = return . id
     }
   where
     go :: InvalidRequest -> IO ()
diff --git a/http-proxy.cabal b/http-proxy.cabal
--- a/http-proxy.cabal
+++ b/http-proxy.cabal
@@ -1,5 +1,5 @@
 Name:           http-proxy
-Version:        0.0.1
+Version:        0.0.3
 License:        BSD3
 License-file:   LICENSE
 Author:         Michael Snoyman, Stephen Blackheath, Erik de Castro Lopo
@@ -20,8 +20,9 @@
   simultaneous connections and is independent of the size of the files being
   uploaded or downloaded.
   .
-  Eventually, features like logging, request re-writing, disk caching etc will
-  be made available via caller provided functions in the Settings data type.
+  The Settings data type provided by the library allows the caller to supply
+  a functions for exception reporting and request re-writing.  Eventually, this
+  capability will be expanded to allow options logging, disk caching etc.
 
 flag network-bytestring
     Default: False
@@ -32,12 +33,10 @@
                    , wai                           >= 0.4      && < 0.5
                    , enumerator                    >= 0.4.8    && < 0.5
                    , http-enumerator               >= 0.7      && < 0.8
-                   , blaze-builder-enumerator      >= 0.2      && < 0.3
                    , transformers                  >= 0.2.2    && < 0.3
                    , blaze-builder                 >= 0.2.1.4  && < 0.4
                    , http-types                    >= 0.6      && < 0.7
                    , case-insensitive              >= 0.2
-                   , unix-compat                   >= 0.2
   if flag(network-bytestring)
       build-depends: network               >= 2.2.1.5 && < 2.2.3
                    , network-bytestring    >= 0.1.3   && < 0.1.4